SenseClusters

SenseClusters is a package of (mostly) Perl programs that allows a user to
cluster similar contexts together using unsupervised knowledge-lean
methods. These techniques have been applied to word sense discrimination,
email categorization, and name discrimination. The supported
methods include the native SenseClusters techniques and Latent
Semantic Analysis.

You can see a
video tutorial entitled "Language Independent Methods of Clustering
Similar Contexts" from EACL 2006 that introduces SenseClusters
(135 minutes).